Environmental Organic Chemistry provides a profound understanding of how molecular processes and macroscopic transport phenomena determine the distribution in space and time of organic compounds released into natural and engineered environments. By explaining in a pedagogical way how to relate the structure of a given chemical to its physical chemical properties and intrinsic reactivities, by providing the necessary background knowledge on the chemistry and physics of microscopic and macroscopic environmental systems, and by introducing simple modeling approaches, the reader is able to quantify mass transfers, transformations, and transport processes at each level.Compared to the 2nd edition, the 3rd edition provides a more holistic and easily teachable description of phase partitioning and transformation processes, as well as a more focused and tailor-made presentation of physical and mathematical modeling aspects. Furthermore, four new chapters have been added that are hard to find in other textbooks: (i) a close look into the amazing world of environmentally relevant anthropogenic chemicals; (ii) a summary of the most important physical and chemical properties of environmental compartments; (iii) a quantitative treatment of aerosol-air partitioning and the role of aerosols in determining the residence time of organic chemicals in the atmosphere; and (iv) an introduction to compound specific isotope analysis (CSIA) and its application to assess organic chemical transformations in laboratory and field systems. Finally, although designed as textbook, with over 1500 references, the 3rd edition offers a unique overview of the pertinent literature in this broad field.